Don B. Robertson

[Industry Knowledge] Evaporation and crystallization process for preparing anhydrous sodium sulfate by dehydration of mirabilite! _ Equipment

Original Title: [Industry Knowledge] Evaporation and Crystallization Process for Preparation of Anhydrous Sodium Sulfate by Dehydration of Glauber’s Salt! Evaporation and crystallization technology for preparing anhydrous sodium sulfate by hot melting and dehydration of mirabilite 1. Type selection The main evaporation equipment of the process adopts a forced external circulation triple-effect evaporator, and the equipment has the characteristics of stable operation, convenient operation and reasonable energy consumption. As the sodium sulfate solution has a certain degree of corrosiveness, it is recommended that the main material of the evaporator is 304 stainless steel in order to improve the service life of the equipment. 2. Working principle Because the mirabilite will lose crystal water at 70 ~ 80 ℃, the process of hot melting, evaporative crystallization,molecular distillation systems, centrifugal separation and fluidized bed drying is selected. Firstly, sodium sulfate decahydrate is lifted to a quantitative feeder bin by a belt conveyor, and is evenly added into a hot melting tank by the quantitative feeder,cbd centrifugal extractor, the temperature is maintained at 70-80 deg C by the heat exchange of an external heater of the hot melting tank, wherein part of sodium sulfate is dissolved in the own crystal water to form a saturated solution, and the crystal slurry mixed solution of anhydrous sodium sulfate crystals and supersaturated sodium sulfate solution is obtained. The crystal slurry mixed solution is sent to a thickener by a transfer pump; the supernatant of the thickener is subjected to three-effect parallel-flow evaporation and crystallization, and then is subjected to solid-liquid separation in a centrifuge and drying in a fluidized bed to obtain an anhydrous sodium sulfate finished product; and the finished product is weighed and packaged. The filtered mother liquor is transferred to the mother liquor tank and then re-pumped to the evaporator for further evaporation and crystallization. The whole process is continuous feeding and discharging. Main equipment 1. Hot melting tank According to the nature of mirabilite, cbd crystallization equipment ,nutsche filter dryer, 10 crystal water will be lost at 70 ~ 80 ℃, so first of all, solid mirabilite needs to be heated from room temperature to 70 ~ 80 ℃, and fully heated and dissolved, which requires enough heating area and thermal melting equipment with high heat transfer efficiency. After calculation according to the handling capacity, select a set of hot melt equipment with reasonable volume and sufficient heat exchange area. 2. Evaporator The process adopts a forced external circulation triple-effect evaporator, which has the characteristics of simple cleaning, high heat transfer coefficient, high evaporation intensity, difficult wall formation and convenient operation. Expand the full text 3. Thickener and mother liquor tank The thickener can not only eliminate the supersaturation of sodium sulfate concentrated crystal slurry and make the crystal grow further, but also play a buffer role in the centrifuge and the preceding dissolving tank. The thickener is provided with an agitator system in order to prevent physical accumulation of solids at the bottom. The mother liquor tank not only can be used as a storage tank for centrifugal mother liquor, but also can play a role in buffering the clear liquor from the upper part of the thickener, and the mother liquor tank needs heat tracing and stirring. 4. Centrifuge In the solid-liquid separation process, it is recommended to select the piston pusher centrifuge, which is easy to operate, with high automation and low labor intensity. 5. Fluidized bed dryer The solid after centrifugal separation is conveyed to the vibrated fluidized bed dryer by the feeder, and the hot air after steam heat exchange is used as the heat source,hemp extraction centrifuge, and the dried product is obtained after drying and cyclone dust removal by the fluidized bed dryer. 6. Vacuum system and centrifugal pump The vacuum pump can be a water ring vacuum pump, and the condenser is an indirect condenser, which can separately recover and treat the evaporated condensed water. Centrifugal pump adopts hot water chemical process pump. (Evaporation Crystallization Technology) Return to Sohu to see more Responsible Editor:.



I'm sorry, but we no longer support this web browser. Please upgrade your browser or install Chrome or Firefox to enjoy the full functionality of this site.